We must act globally if we plan to contain the AIDS pandemic. This requires a commitment to international research. CAPS has developed a model program of collaborative prevention science involving researchers in developed and developing countries. Over the past seven years, we have collaborated with 50 developing-country scientists from Africa, Asia, Latin America, and Eastern Europe to design and implement AIDS prevention research projects in their home countries. Width our help these collaborating scholars have been extremely successful in completing their research protocols and disseminating their findings through international conferences and the scientific literature. Their research has made significant contributions to our understanding of social, behavioral, and epidemiologic factors affecting AIDS prevention; it has influenced policy and practice in countries around the world. Over the next five years, we propose to strengthen and refine the CAPS program of collaborative HIV prevention research in developing countries by consolidating existing successful structures and beginning several new initiative. . In three of the coming five years (years 12, 13, and 15), we will host new groups of 10 developing country scientists to work with us at CAPS to design collaborative research protocols. We will provide them with funding for data collection in their home countries and ongoing technical assistance during project implementation. In two of the next five years (years 11 and 14), we will bring groups of 10 of our most successful collaborators back to CAPS to analyze the data collected in their studies, prepare manuscripts, and design new collaborative studies. A new Innovative Intervention Initiative will result in four additional collaborative intervention studies each year to enhance the productivity and effectiveness of selected previous scholars. Our program's international reputation for excellence will enable us to recruit first-rate scholars who will produce high-quality research and make important contributions to AIDS prevention globally. With strong ties to the CAPS Science, Ethics, Policy, and TIE Cores and the new CAPS program of Collaborative HIV Prevention Research in Minority Communities, we will take full advantage of the unique resources available at CAPS, ensuring high- quality, theory-based research and rapid dissemination of findings to other AIDS researchers, prevention workers, and policy makers, both domestically and internationally.